Automatic telephone-exchange system.



AUTOMATIC TELEPHONE EXCHANGE SYSTEM.

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lnv/enzar's G. A BETULANDER & N. G. PALMGBEN.

AUTOMATIC TELEPHONE EXCHANGE svsmw,

APPUCAUON FILED DEC. 20. [EH3 I l lfiz 55fi Patented Nov. 3%, 1915.

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mmmmml e. A. BETULANDER & N. e. PAIMGREN.

AUTOMATIC TELEPHONE EXCHANGE SYSTEM.

APPLICATION FILE!) DEILZO, I9I3.

' Patented Nov. 30, 1915.

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G. A. BETULAN DER & N. G. PALMGREN. AUTOMATlC TELEPHONE EXCHANGE SYSTEM.

APPLICATION FILED DEQZO, 1913. Q 1 1,162,556. Patented Nov. 30, 1915.

4 SHEETS-SHEET 4.

a n sra'rns PATENT onnion.

GOTTHILF ANSGARIUS BETULANDER, F SC'DLBTfiBNS VILLASTAD, AND NILS GUNNAR PALIVIGRE N, OF STOCKHOLIVI. SWEDEN, ASSIGNORS, BY DIRECT AND MESNE ASSIGN- MENTS, TO THE BETULANDER AUTOMATIC TELEPHONE COMPANY, LIMITED, OF

LONDON, ENGLAND.

AUTOMATIC TELEPHONE-EXCHANGE SYSTEM.

, Specification of Letters Patent.

Patented Nov. 30, 1915.

Application filed December 20, 1913. Serial No. 807,925.

T 0 (M whom it may concern Be it known that we, Go'rrmnr ANsoAnrUs BETULANDER, a subject of the lung of Sweden, and resident of Villa Castor, Sod

selectors being in mechanical as well as electrical respect considerably simpler than the usualselectors with shifting movement in two directions (for instance the, Strowger selectors). Also such systems have been proposed in which the interconnections are established by means of relays only. However, the systems of said kinds heretofore known have the disadvantage that the number of selectors or relays respectively is relatively large, which fact reduces to some extent the worth of those advantages gained by the greater simplicity of the connecting means.

The presentinvcnticn has chiefly for its object to reduce the number of connecting elements necessary in such systems. I According to this invention the said object is attained by a particular arrangement of the junction lines at the central exchange and by a corresponding arrangement of the connecting means used for effecting the interconnections.

The invention consists in providing intermediate lines between a group of incoming lines and the appertaining outgoing lines of the same group-selecting stage, said intermediate lines having at their disposal different lines of each numerical roup of outgoing lines. The outgoing lines are thereby in respect of their accessibility distributed among a number of intermediate lines. As, however. all the intermediate lines are accessihle to the incoming lines evcrv one of the latter a possibility of being connec ed with any one of the outgoing lines pertaining to the groupof incoming lines in question. In such a line arrangement the selecting operation is effected separately the selecting oi"- the group wanted and an available line of that groupbeing effected before an intermediate line and its connecting means are taken into engagement. In addition to a great reduction of the number of connecting elements a considerable simplification of the wiring is attained inasmuch as the number of multiple-contacts is reduced, as will he explained more closely in the following specification.

Some forms of the invention are illustrated by way of example in the accompanying drawings in which- Figure 1 is a comparativerepresentation of line arrangement according to the known Strowger system. Fig. 2 is a corresponding a rangement according to the present invention. Figs. 3 and 4 show schematically two different forms of the invention when using selectors to e'fiect the connections. Fig. is a diagram of circuits corresponding to the general scheme of Fig. 3.

The principal feature of the invention may at first be explained with reference to I Figs. 1 and 2'. In Fig. 1 is shown a line group Ivithe several lines 4 of which are adapted to be connected with anv one of the lines 1, 2, 3 of a number of (in practical cases usually ten) 'line groups I. II, -III. This condition may be designated, independent of the nature of the means used for" effecting the connections, in the manner shown in the drawing, by normally open contacts 5 adapted to be operated by the connecting means. In the wellknown Strowger system this is eii'ected by each line i being connected to the movable wipers of a groupsclector or-line-selector respectively the contact fields of which contain the terminal contacts of the lines 1, 2. 3 the different horizontal contact rows of said fields then corresponding to the different line groups I, II. III.

Referring now to Fig. 2 it will be seen that, according to the present invention. intermediate lines 6 are provided between the incoming lines 4- and the outgoing'lines 1. 2, 3 each of said intermediate lines being adapted to be connected at one side with any calling line at through contacts 7, at the other side with a line i, 2 or 3 of any wanted group I, II or III respectively through contacts S the arrangement being further characterized by ditlerei'it intermediate lines having at their disposal different lines 1, 2 or 3 in each group I, II or III respectively. In such an arrangement an intermediate line must, evidently, be marked engaged not only when it is engaged itself but also when the appertaining outgoing line of the group wanted is engaged. This rendered possible according to this invention by first effecting the selecting operation, thereby determining the intermediate line to used and then separately effecting the connection at both sides of the intermediate line selected. The connections'may for instance be effected by means of selectors allotted individually to the several incoming lines 4 and to the several intermediate lines, the selectors allotted to the lines 4 then effecting the connections between the incoming lines 4 and the intermediate lines 6 and the selectors allotted to the intermediate lines efiect mg the connections between the intermediate lines 6 and the outgoing lines 1, 2, 3. The connections may also be effected by means of relays each contact? and 8 being then operated by a-relay. The selecting and ergizing of the different relays, respectively is effected for instance by means of a groupselector common to. all incoming lines t, which selector upon a call is connected ath tomatically to the calling dine and then operates in response to tl dhhililting-impulses' The operating circuits of the selectors or relays to select the desired group I, II orIIlE.

respectively are controlled. by a testing device which, after the group-selector has been shifted, is connected with the test wires of all the lines of the group selected said testing device thereby affecting the operating circuits in such a manner that only; the connecting elements, corresponding to an accessible line of tie group selected are operated to establish the connection, as will be fully explained below.

t will be seen, when comparing Figs. 1 and 2, that the number of contacts (5 or 8 respectively) necessary for the connections between the line groups I, II, III and IV is less in the arrangement of Fig. 2 than in the corresponding arrangement of Fig. l, and that-isthe principal advantage of the present invention inasmuch as for instance two selectors each adapted for ten lines and having single shifting movement may be substituted for one selector with a capacity of one hundred lines and having double shifting movement. Furthermore, only by this arrangement of intermediate lines it has been possible, in such systems where the connections are effected by means of restarting of the different selectors or the on lays only, to reduce the number of relays in such a degree as to make systems of that kind practicable. By the reduction of the number of contacts the 'iring is, evidently, simultaneously simplified.

The invention is, evidently, not restrictedto the arrangement shown in Fig. 2 where there are many intermediate lines as the number of lines of each group I, II, III and IV. For instance, the number of the intermediate lines may, if desired, be increased whereby one and the same outgoing line will be assigned to two or more intermediate lines and, further, each intermediate line may have at its disposal a plural number of lines in each group, so that for instance the first and second lines of each group I, II and III are assigned to the first intermediate line, the second and third line of each group to the second intermediate line, and so on.

Fig. 3 shows schematically the most im- I portant parts of a selector frame of an ex- I cable 12 partly to pro-selectors 13, partlyto the contact fields 15 of the line selectors 14. he pro-selectors l3 are adapted to select an idle primary connecting selector among ten such selectors pertaining to the first selector group 9 said primary selectors 17 being connected to a common contact field 16 consisting of transversal contact Wires. The primary connecting selectors L? are adapted to select an accessible secondary connecting selector 20 said secondary selectors being connected to the contact iield 18 of the primary selectors through In the present in-.

intermediate lines 19. stance ten secondary selectors are shown but their number may be varied in correspondence to different trafiic conditions; we group-selectors 21 are connected to the two first contact wires of the contact field18 only one of these selectors being represented. he number of the group-selectors may be suited to the maximum number of simultaneously existing calls. The group-selector has eleven contact actuating arms provided one above the other on a rotatable, vertical shaft and operating in the corresponding horizontal rowsof contacts of the contact field 2:2. The contacts of this field are connectcd to the test wires 23 of the junction tion line of each group 24, 26.

lines 24, 25-26 extending to the different thousands groups, in such a manner that the test wires of the ten junction, lines 24: of the first thousands, group enter into the first vertical row of contacts; the test wires of the ten junction lines'25 of the second thousands group into the second vertical contact row of the contact field 22 and so on. Contact plates are inserted between the several horizontal rows of contacts said contact plates being connected through wires 27 to ten corresponding relays (not shown) allotted to the different secondary selectors 20. The contacts ofthe undermost horizontal row of the contact field 22 are connected to marking contacts in'the contactfields 29 of the selectors 20 said fields 29 also containing the terminal contacts of the junction lines 24, 2526. Each second ary selector 20 has at its disposal one junc- The junction lines 24 are each connected with a primary connecting selector 17 of a second selector group 10 on the same frame, which belongs to the first thousands group and the junction lines 25 are each connected with a- ..pr1mary connecting selector 17 of the second selector group 10 in 'a frame belonging to the second thousands group, and so on. The selector group 10 is similar to the group .9 except that the pre-selectors 13 and the contact field 16 are omitted. The junction lines 30, 31-32 coming from the contact fields 29 of the second group 10 extend to different frames belonging to the first thou sands group. The junction lines of the first group 30 are connected with ten corresponding line selectors 14- on the first frame, which belongs to the first hundreds group. and the junction lines of the second group 31 are connected with ten corresponding line se-' lectors on the frame belonging to the second hundreds group, and so on.-

"lhe connecting operation is performed substantially in the l' OllOWIIIfI manner. For

the. sake of simplicity it may be presumedthat' connection with a :subscribers line within the same hundreds group is desired the whole connecting operation then taking place \vithinthe same frame. Upon taking off the receiver atthe substation the correspending pro-selector l3 'sstarte'd to connect the calling suhscrihers line with an idle primaryselector -17.

'lhelatter is then iin mediatelv operated to effect connection "with an idle. first group-selector 2-1 the shaft of which is now rotated for instance one step it the ubscriberwanted belongs to the first thousandsgroup. The group selectorcauses a secondary selector 20 at the time available to operate. said selector connecting the corresponding: intermediate line 19 to that one of the iunction line allotted to this selector. i

which belongs to the first group "34 this line li:\\'lIi L' been marked h the group selector by actuating the corresponding nndermost contact of its contact field. The selecting of an idle secondary selecton having at its disposal'an idle junction line of the group selected; is effected by means of the abovementioned relays allotted to the secondary selectors which relays control the starting circuits of the secondary selectors. Said relays are operated by the group selector to cut off those secondary selectors the. junction lines of which, belonging to the group in question. are already engaged, so that only the first one of the available secondary selectors may he started. If for instance the three first secondary selectors 20 are engaged and the two next selectors can not be used theircorresponding junction lines of the group in question being engaged in other frames. while the fifth selector and its corresponding junction line are free, only this fifth selector is started all other selectors remaining inactive. At the same time as this selector is started or immediately after the shifting of the selector has been finished the of the first group 24 and thus with a corresponding primary selector-17 of the selector group 10. The selector last mentioned now operates in the manner described. at first to select an idle second group-selector 21 and then to connect the incoming junction line with a secondary selector 20 in the meantime selected and shifted through the cooperation of the group-selector and the relays whereby connection is effected with a line selectorll of the same frame. suitably has shifting movement in two directions, has atits disposal all the subscribers lines connected to this frame and is now, operated to complete the connection with the wanted subscriber-s line. i

' In full anto'matic svstems the pie-selectors 13 may. if wanted. themselves constitute the primarv connecting selectors 17 of the first selector group 9 the contact field 16 being then omitted. In semi-automatic systems, hmvever, the arrangement shown in Fig. 3 may advantageously be used the pre-selectors 13 then sin'iultaneously serving to select a disengaged imerator. Fig. 4 shows schematically another form of the invention as applied to an installation for 1000 subscribers. The exchange comprises ten selector frames three of which being shown in the drawing. Only those selectors ran-responding to the groups 10 and 11 of Fig. 3 are provided on each frame the. pie-selectors 13 of Fig. i constituting the primary connecting selectors 17 of Fig. 3.

This selector, \vhiclr The essential difference between the arrangements according to Fig. 3 and Fig. 4 consists in that the secondary selectors 20 of Fig. 4 are connected to the junction lines 30, 3l-32, while the intermediate lines 19 are connected at the corresponding end to the contact fields 29 in such a manner that the ten intermediate lines 19 of the first frame are connected to the different first sets of contacts (the uppermost horizontal row of contacts) of the first frame, the intermediate lines of the second frame connected to the different second sets of contacts of the second frame, and so on, the corresponding contact fields 29 of the difierent frames being connected in multiple. Further, the relay wires 27 are connected to the vertical rows of the group-selector contactfield s,

while the contact plates provided between the difierent horizontal rows are connected to the test wires 23 oftheintermediate lines l9'extending from the same frame. Only four of the secondary selectors 20 are shown I in the drawing though in fact there are ten or more such selectors.

' The connecting operation is the same as described with reference to Fig. 3, a preselector 13 of the first frame for instance upon a call at first selectingan idle groupselector 21 the shaft of which is then rotated two steps, if forinstance connection with a subscribers line "belonging to the second frame is to be established. Upon actuating the corresponding contacts of the groupselector' field the test wires 23 of the intermediate lines 19 belonging to the first frame are connected through wires 27 to the relays allotted to thesecondary selectors 20 of the second frame. By the action of these relays the first available secondary selector '20 of the second frame is now started. Thecorresponding undermost'contact of the groupselector field simultaneously effects such a marking in .the contact field of the secondary selector in question that the latter is "stopped at the first set of contacts thus.

I establishing connection with'the corresponding intermediate line 19 extending to the first framef Immediately after the preselect-or '13 again operates-to find the intermediate line just mentioned whereby connection with one of the junction lines 31 and throughbnat one with a line selector 14 is attained this line selector then operating to completethe connection with. the wanted subscribers line.

AS may be seen from Figs. 3 and i it is immaterial whether the secondary selectors.

' the last instance the junction lines or the 20 are connected to'the junction lines or to.

the intermediate lines. The primary selectors 17 may likewise be connected either to the junction lines (or subscribers lines respectively) or to the intermediate lines. In

subscribers lines respectivelyterminate in For instance a searcher may be assigned to each group-selector said searcher hunting out the calling line and connecting the group-selector to the same.

Fig. 5 illustrates the circuit arrangements i for effecting connections in one connecting section, for instance 10 of Flg. 3. The primary selectors 17 and the secondary selec tors 20 are of the ty e described in the patent application No. 54273 (filed March,

14, 1913). They-are provided with three electro-magnets, viz., a main magnet 33, an

auxiliary magnet 34-and a tilt magnet 35.

The shifting operation is elfected by the magnets 33 and 35 being energized thereby releasing the member supporting the contact wipers of the selector. Said member, upon being released, drops and continues its descendent movement until the private wiper finds an idle-junction line the magnets 33 and 35 being then deprived of current so. that the supporting member is stopped in, the corresponding position.

During the movement the line wipers are keptout of contact with the contact field by the tilt magnet 35. The restoring of the selector to normal position is effected by sending intermittent current through the main magnet 33 while the magnets 34 and 35 are energized continuously.

The shifting member of the group-selector 21 consists, as stated above, of a vertical, rotatable shaft supporting eleven horizontally projecting arms arranged one above the other and each operating'in a corresponding row of contacts 36 of the contact field 22. The shaft is rotated step-by-step in any known manner by means of an electro-magnet 37 and is restored by means of an electro-magnet 38. During the shifting and restoring operations the arms are kept out of contact with the corresponding-rows of contacts by means of an electro-inagnet 39 the latter upon energizing 'raisingJthe shaft and its arms, Each row ofcontacts comprises a contact plate 40 and ten c'ontact springs 41 mounted with interposed insulation on the said plate. As the magnet I 39, after the selector has been shifted, is depressed the projecting arms then actuating the corresponding contact springs 41, so that energized for a moment the shaft .is de I the ten upper springs make contact with the subjacent contact plates 40 while the undermost one opens the corresponding contact. However, in order to make the circuits plain the contacts are drawn in such a manner as if the making and breaking of the contacts were effected in horizontal direction. The contact plates 4:0 are connected toearth, the undermost one directly and the other through relays l2 allotted to the different secondary selectors 20. The contact springs 4C1 o't'the uppermost row are connected to the corresponding test wires 43 of the outgoing junction lines terminating in the contact field 29 of the shown first secondary selector 20, the contact springs of the subj acent row to the test Wires 4% of the outgoing junction lines assigned to the second secondary selector, and so on. The contact springs "ll of the undermost contact row are connected through wires 46 to the marking contacts of the secondary selectors said marking contacts being connected in multiple Within the same frame. In this instance three group-selectors are supposed to be assigned to each group of ten primary selectors. The battery, the positive pole of which isconnected to earth, is not illustrated. Instead of it pole designations (earth and minus) are placed at the ends of the Wires. The current transmission necessary for ett'ecting aconnection in a connecting section, is such that at first both line branches are connected to earth and then a contact in one branch is opened and closed repeatedly. Thus, immediately after the calling subscriber has connected his line to a line 47, 48 leading to a primary selector 17 a circuit is closed extending from earth at the line branch d7 through this line branch, 'the carrier operated contact 49 of. the selector 17 and further partly through the contact 50 and a relay 51, partly through the main magnet 33 and partly through the contact operated by the auxiliary magnet 34; and the tilt magnet 35 to the battery. Upon the closure of this circuit the primary selector 1'? is started. The relay 51. upon energizing, puts itseli into a locking circuit through the contact and remains thus energized even after the Wiper carrier has left its normal position and opened the contacts 49 and 50 The tilt magnet closes the contact 54 thereby connecting itself to the private Wiper 55 through the contact 52 of the auxiliary magnet 33.

As long as the primary selector 17 is hunting for an idle group-selector 21 the flow of current through'the magnets .33 and 35 is maintained through the private Wiper 55 and the-earthed test Wires 56 of the engaged group-selectors. In this instance it may be supposed that the first group-selector is free. Wiper 55 reaches the corresponding'test con- Accordingly, as the private group-selector being in this way marked as engaged.

As the Wipers 58 and 59 engage the contact field two circuits are'closed, one

tending from the earth at the line branch 47 through the wiper 58, wire (ll, a shaft operated contact 62 closed in the normal position of the group-selector, and further parallelly through tivo relays and (El to the battery, the other extending from earth at the line branch 48 through Wiper 59, Wire 65 and the shitting magnet 37 ot' the group-selector to the battery. Although said magnet 37 attracts its armature upon the closure of the circuit last mentioned yet the shaft of the group-selector is not rotated until the magnet releases its armature. The relay 63, upon energizing, cuts itself and thereby the slow acting relay 64. into a locking circuit through. the contact 66 and the lifting magnet 39 into a circuit through the contact 67.

first line group is desired. Accordingly the current flowing in the line branch 48 is now interrupted while the line branch t? is maintained current carrying. The shifting inagnet 37 of the group-selector thereby de'cnerso that the shaft of the selector is rotated one step. Immediately after the circuit extending over the line branch 4:? is also broken so that the relays 63 and 64 are deprived of current the relay 03 thereby 1nstantly releasing its armature, while the slow acting relay 6% for a short time keeps its armature in attracted position. Consequently, the lifting magnet 39 is deenergizcd thereby causing the group-selector arms to operate the corresponding contact springs 41 and close a contact (38. In. closing'the contacts 40, 41 all the ten junction lines of the first group are tested. Should any one of these junction lines, for instance the second, be engaged a circuit is closed from earth through the relay at the second secondary selector, wire 69, contact 40, ii of the second IOW of contacts, Wire 70, the corresponding test Wire 44 and further through the auxiliary magnet 34 of the secondary selector 20 corresponding to the junction line in question to the battery. The relay 42 energizes upon the closure of this circuit thereby opening the contact :75 and cutting oil? the corresponding secondary selector, as Will be fully explained below. In this instance may be supposed that the first junction line ais Well as the first secondary selector 10 are disengaged. The corresponding test Wire 43 is then disconnected from the battery and, consequently, the re lay 42 at the first selector 10 remains deenergized. Thus, a circuit is closed extending from earth through the contact 72, contact 73 of relay 6%, contact 68, wire 7%, contact 75 of relay-42, contact 76 and further parallelly partly through the main magnet 33, partly through a contact 77 operated by the auxiliary magnet 34: and a relay 78 and partly through the contact 79 and the tilt magnet to the battery. The selector 20 is started upon the closure of this circuit, and simultaneously the relay 78 attracts its armature thereby putting itself into a lock ing circuit through the contact 80 and opening 'a contact 81 for the purpose of preventing the starting current, after having started the selector 20, from passing through the contact 82, Which is closed as the selector leaves its normal position, and through the contact 81 "to the next idle selector, which then would be started too. lector 20 now hunts for that junction line the marking contact of which has been disconnected from earth by the group-selector, thus, in this instance the first junction line 83, 841. During the shifting movement the Wipers 85, 86 and 87 are kept out of engagement With the contact field While the private Wiper 88 always engages the con: tact field. Since now the first test contact '45 is disengaged from earth the magnets 33 and 35 are deenergized even upon opening the contact 76. The contact Wipers are.

therebystopped in the first contact posi through the contacts 93 and 81, and so on.

Immediately after the shifting of the first secondary selector 20 the relay 64: releases its armature the locking circuit of the relay '78 being thereby broken at the contact 73.

The restoring inagnet38 of the group selector simultaneously receives current through the contacts 72 and 94. This magnet there by cuts in the lifting magnet 39 at the contact 95 and releases the shaft of the group selector so that this one will be restored to normal position by the action ot-a. spring.

During the restoring movement the group selector is marked as engaged by its test Wire 56 being connected to earth through the contacts 96 and 72. The latter are opened in The started seconnected to earth. A circuit is thereby closed extending from earth through line branch 47, contact 97 of relay 51, contact 98 and further parallelly partly through the magnet 33, partly through the contact 52 andthe magnet 35 of the primary selector 17 to the battery. Upon the closure of this circuit the selector 17 is started for the second time the said circuit, as long as the Wipers are moving through the three contact positions pertaining to the group-selectors, being maintained through the contact 98 which is adapted to be opened when the Wipers reach the contact position of the first intermediate line. Sincethe test wire 99 of this intermediate line has been disconnected from earth at the contact 100 by the shifting of the corresponding secondary selector, 20 the primary selector is stopped in the corresponding contact position. Hereby the connection is prolongated to a. line selector or to a primary selector of the next connecting section respectively; If, however, the primary selector had to hunt for instance for the fifth intermediate line,'

the flow of current through the'magnets 33 and 35 ofthat selector would be maintained through the private Wiper 55 and the test wires 99 of the four first intermediate lines as these test wires then would be connected to earth either through the contact 100 of the corresponding secondary selector or through the private Wiper 55 and the contact (i0 of another primary selector connected to the corresponding intermediate line.

The restoring of the selectors is effected by one or the other subscriber by putting earth to the restoring wires 101-, 91 and 92. The circuit of the magnet 34k of the primary selector is thereby closed thrbugh the contact 102 actuated by the wiper carrier. magnet, upon energizing, puts the magnet 33 in a circuit containing the contact 103 and an interrupter 104. Further, the circuit of the tilt magnet 35 is closed at the contact Consequently, the primary selector 17 1sv restored to normal position in which the restoring circuit is broken at the contact operating, putting the main magnet 33 into a circuit including thecontact 106 and the interrupter 10% and simultaneously putting itself in a locking circuit through the contacts 107, 108 and 109. Further, the circuit of the tilt magnet 35 is closed through the contacts 108 and 109. Consequently, the secondary selector is restored to its normal position in which the restoring circuit is broken at the contact 109. During the re- Said 102. secondary selector 20 is'restored m a similar manner the magnet 34, upon storing period the secondary selector is marked as engaged by its test wire 99 being connected to earth through the contact 110.

Having now described our invention, What we claim as new and desire to secure by Letters Patent is:

1. A telephone exchange system having in each group-switching section a plurality of numerical groups of outgoing lines, a number of incoming lines each adapted to be numerical groups of outgoing lines, a number of incoming'lines each adapted to be connected with anyone of the lines of said groups, intermediatejunction lines provided between said incoming and outgoing lines and having at their disposal different lines of each numerical group, connecting means individually allotted to the various lines and adapted to effect the connections at both ends of the intermediate lines and separate selecting means allotted in common to the incoming lines and adapted to select the group wanted and an intermediate line available for the connection wanted.

3. A telephone exchange system having in each group-switching section a plurality of numerical groups of outgoing lines, a number of incoming lines each adapted to be connected with anyone of the lines of said groups, intermediatejunction lines provided between said incoming and outgoing-lines and having at their disposal different lines of each numerical group, connecting means individually allotted to the incoming lines and adapted to'effect the connections be-- tween the incom ng lines and the intermediate lines, connecting means individually allotted to the intermediate lines and adapted to effect the connections between the intermediate lines and the outgoing lines and separate selecting means adapted to select the connecting means available for the con nection wanted.

4. A telephone exchange system having'in each group-switching section a plurality of numerical groups of outgoing lines, a number of incoming lines each adapted to be connected with anyone of. the lines of said groups intermediate j unction' lines provided between said incoming'and outgoing lines and having at their disposal different lines of each numerical group, connecting means individually allotted to,the incoming lines and adapted to effect the connections between the incoming lines and the intermedi-' ate lines, connecting means individually allotted to the outgoing lines and adapted to eifect the connections between the intermediate lines and the-outgoing lines and common selecting means adapted to select the connecting means available 'for the connec- 4 tion wanted, I

5. A telephone exchange system having in each group-switching section a pluralitv of; numerical groups of outgoing lines, a num ber of incoming lines each adapted to be connected with anyone of the lines ofl's'aid groups, intermediate junction linesprqrided a between said incoming and outgoing lines and having at their disposal different lines of each numerical group, a plurality of selectors common to the incoming lines, con- 35 necting means individuallfy allotted to,theincoming lines and means I or operating said with the intermediate line to-be used.

6. A telephone'exchange system having in each group-switching section a plurality of numerical groups of outgoing lines, a number of incoming lines each adapted to be connected with anyone of the lines of said groups, intermediate lines provided between said incoming and outgoing lines and have ing at their disposal dlnerent lines of-each numerical group, connecting 'means for effooting the connections at both ends of the intermediate'lines, separate selecting means for selecting the group wanted, operating circuits for said connecting means and separate testinglmeans controlling said circuits and adapted to select the connecting means availablefor the wanted connection.

In witness whereof, We have hereunto signed our names in the presence of two subscribing witnesses.

GOTTHILF ANSGARIUS BETULA NDIrR,

NIliS GUNNAR PA'LMGREN Witnesses:

' Ronnn'r APELGREN,-

GRETA PRLEN.

i connecting means first to, connect the ap; f

pertaining incoming line with oneof said selectors and then,to effect the connection 90 

